Sex education where demonstrations for the purpose of modeling proper sexual technique, safer sex protocols and better communication are performed usually for a live audience who's encouraged to watch and ask questions. Demonstrations may or may not include nudity or explicit sexual contact, but often do.

"Show-n-Tell Sex Ed is such a better way to learn how to be a sex ninja than watching porn."

"I went to a Show-n-Tell Sex Ed workshop where the sex educator totally hand-fucked a melon with a latex glove and some lube!"

"That strap-on workshop was a Show-n-Tell Sex Ed class and they pegged a dude in front of me and my gf."